The theory of punctuated equilibrium states that is a species appear in a fossil record, they will become stable over time and can show little changes in evolution as time goes by. An example would be the feline creatures. Although cats and tigers have a different structure in their body, the facial structure and the way they hunt are similar.
An organism that can make its own food is a producer. An organism that obtains energy by feeding on the other organisms is a consumer. Decomposers break down wastes and dead organisms and return the raw materials to the ecosystem.
Answer:
n (a neutron)
Explanation:
For a chemical element:
- The lower subscript indicates the atomic number (the number of protons)
- The upper subscript indicates the mass number (the sum of protons and neutrons in the nucleus)
In the reaction described in the problem, we see that a gamma photon hits a nucleus of Calcium-40, which has
Z = 20 (20 protons)
A = 40 (40 protons+neutrons)
Which means that the number of neutrons is n = A - Z = 40 - 20 = 20
After the reaction, we have a nucleus of Calcium-39, which has
Z = 20 (20 protons)
A = 39 (39 protons+neutrons)
Which means that the number of neutrons is n = A - Z = 40 - 39 = 19
So, the nucleus has lost 1 neutron, which is the particle missing in the reaction.
Answer and Explanation:
The formation of planets ,initially was the result of gradual accumulation of solid matter into the solar nebula. As a result of high temperature in the interior of our solar system, metals and rocks were the only materials to get compressed.
The matter that was volatile could not be compressed so close to the heat energy radiated by the early Sun.
On the outer part of the solar system, solid matter included hydrogen compounds, rocks and metals with a lot of matter for planet formation.
The Giant planets were formed by capturing Helium and hydrogen gases as well whereas the terrestrial planets being much more smaller are made up of mainly rocks like silicates and metals like iron.
The moons of terrestrial planets like that of Earth is also terrestrial in nature consisting of rocks and metals as the constituent material while that of giant planets consist of frozen water in half the proportion and the other half is rocks and metals.
